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Base your answers to questions 2 on the information below and on your knowledge of biology.

Since 1980, the vulture population in India has declined from 40 million to 60 thousand due to poisoning by a pain reliever used in cattle. If only 1% of the cattle carcasses fed on by vultures are animals that have been treated with the drug, it can lead to a drastic decline in the vulture population. The grim picture is that over 10% of the carcasses have been found to contain this drug.

Vultures feed exclusively on the carcasses of dead animals. This helps to prevent the spread of diseases such as rabies and anthrax among wildlife, livestock, and humans. Without as many vultures present, other scavengers such as dogs have moved in and taken advantage of the newly available food. The abundance of these other scavengers has led to an increase in the number of cases of human rabies and an outbreak of tuberculosis, anthrax, and foot-and-mouth disease. These diseases are not spread to humans by vultures.

Base your answers to questions 4 on the information and data table below and on your knowledge of biology.

Measles: Eliminated?

Measles is a highly contagious viral disease. Infected people first experience a fever, cold-like symptoms, and a rash. Several complications can develop, such as ear infections, diarrhea, pneumonia, encephalitis (swelling of the brain), and death. Prior to the widespread use of the measles vaccine in the 1960s, it is estimated that 3–4 million people were infected every year. The Centers for Disease Control and Prevention declared measles eliminated in the United States in 2000. This was accomplished, in part, due to a highly effective vaccination program. However, since 2016 the disease has made a comeback, and there has been an increase in measles cases in recent years.

Directions: Using the information in the data table, construct a line graph on the grid below, following the directions below.

Base your answers to questions 7 on the passage below and on your knowledge of biology.

Polio is a virus that can cause paralysis or death. At its peak, the disease affected about 500,000 people a year worldwide before the development of an effective vaccine in 1955.

When the first polio vaccine was developed, it was tested in experiments using thousands of children as subjects. The children were injected with either the experimental vaccine or given a harmless injection without the vaccine. Only after these extensive tests was the vaccine finally accepted as being successful in preventing the disease.

Although, at this time, polio has been nearly eliminated in the Western Hemisphere, certain countries in the world still report new cases of the disease. Complete elimination of the disease can be achieved in these countries by vaccinating all of the children at the same time with the polio vaccine.

Base your answers to questions 8 on the data table below and on your knowledge of biology.

Base your answers to questions 9 on the passage below and on your knowledge of biology.

A Vaccine to Treat Addiction

A vaccine for cocaine addiction has been developed. This vaccine temporarily blocks the effects of cocaine. The vaccine consists of a cocaine molecule attached to the surface of an inactive, harmless cholera protein.

Since cocaine molecules alone are too small to stimulate the immune system to create antibodies, they are attached to the cholera protein. When people are injected with the vaccine, their bodies make antibodies against cholera. They also make antibodies against cocaine. When cocaine later enters the bloodstream, the antibodies bind to cocaine and prevent it from leaving the bloodstream, so it does not reach the brain. If the drug does not reach the brain, the user does not feel its effect. When antibodies were blocking the cocaine, people who took cocaine didn’t get an effect from it, so the drug lost its appeal. Later, an enzyme breaks down the cocaine and it is flushed out of the body.

One problem revealed by the trial was that only 38 percent of vaccinated subjects developed high levels of antibodies against the drug. Additionally, the vaccine’s protection seems to last for only about two months. Users need to receive booster shots every few months for approximately two years to make a complete recovery from the addiction.

Base your answers to questions 10 on the information below and on your knowledge of biology.

Some viruses can enter cells by first attaching to the cell membrane. The flu virus targets and attaches to the cells of the nose and mouth. The hepatitis virus targets only specific cells of the liver.

Base your answers to questions 11 on the passage below and on your knowledge of biology.

Here, Eat This Vaccine

Munching on bacteria could be a good way to stimulate your immune system. Biologist Simon Cutting of the Royal Holloway University of London has transformed bacterial spores into an edible vaccine. He and his collaborators genetically altered the common bacterium Bacillus subtilis so that it produced harmless fragments of the toxin produced by tetanus. Then his team starved the bacterium so that it turned into a spore — a desiccated [dehydrated] packet tough enough to survive a trip through the digestive tract and into the bloodstream. Most of the mice that inhaled or ate the modified spores were then able to survive a lethal dose of tetanus.

“We selected tetanus because the immunology regarding this disease is well understood,” Cutting says. But engineered bacteria could be similarly tailored to train the immune system to fight anthrax, traveler’s diarrhea, and other illnesses. Edible vaccines would eliminate the need for needles and sterilizing equipment. Moreover, spores can withstand extreme heat and dryness, remaining viable [alive] for thousands of years. Cutting plans to start clinical trials in about two years. If the results measure up, spore vaccines could slash the cost of immunization programs, especially in poor countries where refrigeration is unreliable and transportation can be slow.

Source: http://discovermagazine.com/2003/aug/breakeat/ Here, Eat This Vaccine, by Zara Herskovits August 1, 2003

Base your answer to question 12-14 on the information below and on your knowledge of biology. Base your answers to questions 15 on the information below and on your knowledge of biology.

In an experiment to test the effectiveness of a new vaccine, 50 rats received an injection of equal doses of the vaccine and 50 other rats received an injection of equal doses of a weak salt solution. Two months later, all of the rats received injections that contained equal doses of live, disease-causing organisms.

The experimental results are shown in the chart below.

Base your answer to question 17-20 on the information below and on your knowledge of biology.

An Experimental SARS Vaccine Works in Animals

Scientists reported that they had protected animals from the effects of the SARS virus by using an experimental vaccine. The SARS virus causes an acute respiratory illness in humans and other animals.

This vaccine was sprayed once into the nostrils of each of four African green monkeys. Four weeks later, these monkeys were exposed to the virus that causes SARS. The monkeys showed no sign of the disease in their respiratory tracts. Blood tests confirmed the presence of proteins known as neutralizing antibodies that indicate protection against disease.

The scientists also sprayed a placebo (a substance that did not contain the vaccine) into the nostrils of each of four other African green monkeys. After exposure to the virus that causes SARS, all of these monkeys developed symptoms of this condition.